"""
Gestor de conexiones para Serial, TCP y UDP
"""

import serial
import socket
import time

class ConnectionManager:
    def __init__(self):
        self.connection = None
        self.connection_type = None
        self.dest_address = None  # Para UDP
    
    def open_connection(self, conn_type, conn_params):
        """Abre una conexión según el tipo especificado"""
        try:
            if conn_type == "Serial":
                self.connection = serial.Serial(
                    conn_params['port'], 
                    conn_params['baud'], 
                    timeout=1
                )
                self.connection_type = "Serial"
                
            elif conn_type == "TCP":
                sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
                sock.settimeout(5.0)
                sock.connect((conn_params['ip'], conn_params['port']))
                self.connection = sock
                self.connection_type = "TCP"
                
            elif conn_type == "UDP":
                sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
                sock.settimeout(1.0)
                self.dest_address = (conn_params['ip'], conn_params['port'])
                self.connection = sock
                self.connection_type = "UDP"
                
            return self.connection
            
        except Exception as e:
            raise Exception(f"Error al abrir conexión {conn_type}: {e}")
    
    def close_connection(self):
        """Cierra la conexión actual"""
        try:
            if self.connection_type == "Serial":
                if self.connection and self.connection.is_open:
                    self.connection.close()
            elif self.connection_type in ["TCP", "UDP"]:
                if self.connection:
                    self.connection.close()
        except Exception as e:
            print(f"Error al cerrar conexión: {e}")
        finally:
            self.connection = None
            self.connection_type = None
            self.dest_address = None
    
    def send_data(self, data):
        """Envía datos por la conexión actual"""
        if not self.connection:
            raise Exception("No hay conexión activa")
            
        try:
            if self.connection_type == "Serial":
                self.connection.write(data.encode('ascii'))
            elif self.connection_type == "TCP":
                self.connection.send(data.encode('ascii'))
            elif self.connection_type == "UDP":
                self.connection.sendto(data.encode('ascii'), self.dest_address)
        except Exception as e:
            raise Exception(f"Error al enviar datos: {e}")
    
    def read_response(self, timeout=0.5):
        """Intenta leer una respuesta del dispositivo"""
        if not self.connection:
            return None
            
        try:
            response = None
            if self.connection_type == "Serial":
                # Guardar timeout original
                original_timeout = self.connection.timeout
                self.connection.timeout = timeout
                # Esperar un poco para que llegue la respuesta
                time.sleep(0.05)
                # Leer todos los bytes disponibles
                response_bytes = b""
                start_time = time.time()
                while (time.time() - start_time) < timeout:
                    if self.connection.in_waiting > 0:
                        response_bytes += self.connection.read(self.connection.in_waiting)
                        # Si encontramos un terminador, salir
                        if b'\r' in response_bytes or b'\n' in response_bytes:
                            break
                    else:
                        time.sleep(0.01)
                
                if response_bytes:
                    response = response_bytes.decode('ascii', errors='ignore')
                self.connection.timeout = original_timeout
                
            elif self.connection_type == "TCP":
                self.connection.settimeout(timeout)
                try:
                    response = self.connection.recv(1024).decode('ascii', errors='ignore')
                except socket.timeout:
                    pass
                    
            elif self.connection_type == "UDP":
                self.connection.settimeout(timeout)
                try:
                    response, addr = self.connection.recvfrom(1024)
                    response = response.decode('ascii', errors='ignore')
                except socket.timeout:
                    pass
            
            return response
            
        except Exception as e:
            print(f"Error al leer respuesta: {e}")
            return None
    
    def read_data_non_blocking(self):
        """Lee datos disponibles sin bloquear (para modo trace y netcom)"""
        if not self.connection:
            return None
            
        try:
            data = None
            if self.connection_type == "Serial":
                if self.connection.in_waiting > 0:
                    data = self.connection.read(self.connection.in_waiting).decode('ascii', errors='ignore')
                    
            elif self.connection_type == "TCP":
                self.connection.settimeout(0.1)
                try:
                    data = self.connection.recv(1024).decode('ascii', errors='ignore')
                    if not data:  # Conexión cerrada
                        return None
                except socket.timeout:
                    pass
                    
            elif self.connection_type == "UDP":
                self.connection.settimeout(0.1)
                try:
                    data, addr = self.connection.recvfrom(1024)
                    data = data.decode('ascii', errors='ignore')
                except socket.timeout:
                    pass
            
            return data
            
        except Exception as e:
            print(f"Error al leer datos: {e}")
            return None
    
    def is_connected(self):
        """Verifica si hay una conexión activa"""
        if self.connection_type == "Serial":
            return self.connection and self.connection.is_open
        else:
            return self.connection is not None